// setTimeout(function () {
//   var a = 'hello'
//   setTimeout(function () {
//     var b = 'lagou'
//     setTimeout(function () {
//       var c = 'I❤U'
//       console.log(a + b + c);
//     }, 10);
//   }, 10);
// }, 10);

function p1 () {
  return new Promise(function (resolve,reject) {
    setTimeout(function () {
      var a = 'hello'
      resolve(a)
    }, 10);
  })
}
function p2 () {
  return new Promise(function (resolve,reject) {
    setTimeout(function () {
      var b = 'lagou'
      resolve(b)
    }, 10);
  })
}
function p3 () {
  return new Promise(function (resolve,reject) {
    setTimeout(function () {
      var c = 'I❤U'
      resolve(c)
    }, 10);
  })
}

Promise.all([p1(), p2(), p3()]).then(value => console.log(value))



